package com.itheima.reggie_1.filter;

import com.alibaba.fastjson.JSON;
import com.itheima.reggie_1.common.BaseContext;
import com.itheima.reggie_1.common.R;
import lombok.extern.slf4j.Slf4j;
import org.springframework.util.AntPathMatcher;

import javax.servlet.*;
import javax.servlet.annotation.WebFilter;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

/**
 * 检查用户是否已完成登录
 *      @WebFilter:
 *          设置拦截器名称: loginCheckFilter
 *          设置拦截路径:  拦截所有: /*
 */
@WebFilter(filterName = "loginCheckFilter",urlPatterns = "/*")
@Slf4j
public class LoginCheckFilter implements Filter {
//    创建路径匹配器对象
    private static final AntPathMatcher PATH_MATCHER = new AntPathMatcher();
    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
        HttpServletRequest request = (HttpServletRequest) servletRequest;
        HttpServletResponse response = (HttpServletResponse) servletResponse;
//        1.获取本次请求的URI
        String requestURI = request.getRequestURI();// /backend/index.html
        log.info("拦截到请求: {}",requestURI);
//        设置不需要拦截的路径
        String[] urls = new String[]{
                "/employee/login",
                "/employee/logout",
                "/backend/**",
                "/front/**",
                "/common/**",
                "/user/sendMsg",// 移动端发送短信
                "/user/login",//    移动端登录
                "/doc.html",
                "/webjars/**",
                "/swagger-resources",
                "/v2/api-docs"
        };
//        2.判断本次请求是否需要处理
        boolean check = check(urls, requestURI);
//        3.如果不需要处理则直接放行
        if (check) {
            log.info("本次请求{}不需要处理",requestURI);
            filterChain.doFilter(request,response);
            return;
        }
//        4-1.判断登录状态,如果已登录,则直接放行
        if (request.getSession().getAttribute("employee") != null) {
            log.info("用户已登录,用户id为: {}",request.getSession().getAttribute("employee"));

            Long empId = (Long) request.getSession().getAttribute("employee");
            BaseContext.setCurrentId(empId);

            long id = Thread.currentThread().getId();
            log.info("线程id为: {}",id);

            filterChain.doFilter(request,response);
            return;
        }
//        4-2.判断登录状态,如果已登录,则直接放行
        if (request.getSession().getAttribute("user") != null) {
            log.info("用户已登录,用户id为: {}",request.getSession().getAttribute("user"));

            Long userId = (Long) request.getSession().getAttribute("user");
            BaseContext.setCurrentId(userId);

            long id = Thread.currentThread().getId();
            log.info("线程id为: {}",id);

            filterChain.doFilter(request,response);
            return;
        }
//        5.如果未登录则返回登录结果,通过输出流的方式向客户端页面相应数据
        response.getWriter().write(JSON.toJSONString(R.error("NOTLOGIN")));
        return;
    }

    /**
     * 路径匹配检查本次请求是否需要放行
     * @param urls
     * @param requestURI
     * @return
     */
    public boolean check(String[] urls,String requestURI) {
        for (String url : urls) {
            boolean match = PATH_MATCHER.match(url, requestURI);
            if (match) {
                return true;
            }
        }
        return false;
    }
}
